Biodiesel additive ethyl levulinate synthesis by catalytic membrane: SO4−2/ZrO2 loaded hydroxyethyl cellulose

•Catalytic membranes as new catalyst are used for synthesis of ethyl levulinate.•Ethyl levulinate is synthesized by esterification of levulinic acid with ethanol.•The highest levulinic acid conversion of 89% obtained.•SO4−2/ZrO2 catalytic membrane exhibited effective catalytic activity.

In this study, different catalytic membranes have been improved for use as heterogeneous acid catalyst to synthesize fuel bioadditive ethyl levulinate from levulinic acid and ethanol. Catalyst design was done by wet impregnation method. Catalytic membrane was prepared by solution casting method by loading of catalyst in hydroxyethyl cellulose polymer. Catalytic membranes including tungstosilicic acid hydrate, tungstosilicic acid supported on zirconium oxide and sulfated zirconium oxide were prepared and characterized. According to experimental results, sulfated zirconium oxide loaded catalytic membrane was found more effective when compared to the other catalytic membranes studied. Effects of reaction parameters such as reaction time, catalyst loading on membrane, reaction temperature, catalytic membrane amount, initial molar ratio on the conversion of levulinic acid were also investigated. Pseudo homogeneous second order kinetic model was applied to the experimental data. Activation energies and kinetic constants were determined. The theoretical conversion data were fitted well with the experimental data.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide